Return clean argument keys

[zenangst]

Personally I think it looks kinda weird that the delimiter is included in the arguments dictionary that you get when you resolve arguments. I'd like to strip it out from the key entirely.

Before

Compass.parse(url) { route, arguments in
  XCTAssertEqual("login:{username}:{password}", route)
  XCTAssertEqual(arguments["{username}"], "JohnHyperseed")
  XCTAssertEqual(arguments["{password}"], "secret")
}

After

Compass.parse(url) { route, arguments in
  XCTAssertEqual("login:{username}:{password}", route)
  XCTAssertEqual(arguments["username"], "JohnHyperseed")
  XCTAssertEqual(arguments["password"], "secret")
}

[vadymmarkov]

@zenangst Yeah, totally agree. I was thinking about that too, but forgot to tell you 😄

[zenangst]

@vadymmarkov look, a wild pull request appeared 😎